Picture: Sea ice, Jökulsárlón, Iceland. Credit: Davide Cantelli (Unsplash).
Northwest of Svalbard, north of Norway, an area known as Whalers Bay stays ice‐free in winter despite the negative air temperatures. It has been assumed that this open water is maintained by inflow of warm Atlantic Water along Svalbard’s west coast; however, this mechanism has never been demonstrated quantitatively.
Researchers combined observations and results from modelling to calculate the rate of ice melting necessary to keep Whalers Bay ice‐free, and the amount of heat that must be transferred from the ocean to the ice to sustain such melting.
They concluded the presence of Atlantic Water combined with the occurrence of storms releases the amount of heat necessary to keep the area ice‐free. When the Atlantic Water is close to the surface and its temperature is above about 5oC, storms are no longer necessary to enhance heat transfer and produce the required melting.
As the amount of heat transported by the Atlantic Water and the storm frequency has been increasing over several decades, the researchers expect in the future the ice‐free area will increase, affecting air‐sea‐ice fluxes, water mass transformation, marine ecology, sea ice cover and commercial activity including transportation and fishing.
- Paper: Duarte, P., Sundfjord, A., Meyer, A., Hudson, S. R., Spreen, G., & Smedsrud, L. H. (2020). Warm Atlantic Water explains observed sea ice melt rates north of Svalbard. Journal of Geophysical Research: Oceans, 125, e2019JC015662. https://doi.org/10.1029/2019JC015662